How to add exemplars to metrics generated using opentelemetry SDK?

I’m trying to add exemplars to the metrics generated in my Javascript based API. I’m using the opentelemetry JS API and SDK to instrument my code.

This is my counter.

/**
 * Using a counter to measure the total number of posts received by the API
 */
exports.postCount = apiMeter.createCounter('api.posts.count.total', {
    description: "Total number of posts received",
    unit: "posts"
});

And I increment in conditionally

// inside the condition
postCount.add(1)

How do I add the exemplars using Opentelemetry API? I tried adding my Trace Context as labels like this

postCount.add(1, {trace_id: xxxxeeia});

but I figured later it’s the wrong way to do it.